Advance Chip-Level Module Chip-level Training will be customized for your present knowledge of electronics. If you go through the fundamental track , all the power electronic components will be introduced before we move to the logics section. After you become comfortable with power electronics the logic session follows . It is an intensive coverage into the intricate details of chip-level service of the laptops. This involves detailed circuit tracing , signal analysis , replacement of SMD devices and all the tips and tricks our service engineers acquired from the years of experiences. the session makes you confident enough to chip-level service the new generation notebooks from Lenova , Compaq, HP , Toshiba ,Sony and the like .
Service Technicians entering into the Laptop training course must have experience in the following disciplines
A: I find it is very hard to explain this. actually, it is very simple and can be described in two words: current and singal. read the current change during booting tells you where the machine stopped. check the singals on the different part of motherboard tells what is wrong or what may missing.
Tools are: smd rework station, bga rework station, power supply has current meter. all the rest tools you can find in any radio tv repair shop.of course all the datasheets for the components, especially the schematic diagram, you will find it much difficult without it.
Q:What are common faults on mainboards? Do certain components fail? Is there a trend as to which parts fail quite often?
A: Different maker/model has different common fault. Toshiba S1 is vga chip, and can’t be repaired(well, almost can’t be repaired because the pcb quality is not very good so successful rate is very low). HP DV2000, 6000, 9000, compaq v3000, v6000, dell 1210, all those use nvidia chips have problem on vga chip or north bridge. easy to repair but have to make fan keep spinning after repaired, otherwise will break down in 1 or 2 week again.
hp nx5000, cpu pwm chip dry joint. acer 290, cpu pwm dry joint. hp dv1000, compaq m2000 protection circuit easy to blow up. ibm t40 vga dry joint problem. These are just few of them. every machine has its own common fault. but dry joint is the common problem for all machines. Motherboard repair is not as difficult as people thought, i think much easer than repair a tv.
Q:Dell 1525 Inspiron that says system does not recognize the installed battery this system will not charge the battery.
A:Charging battery in Dell laptop involves two major chips: EC(or someone call it super IO), PWM chip for battery charging. BIOS has no part of charging. Battery communicate with EC through SMB(system management bus??) and EC controls charging PWM. Fix charging problem is very hard in laptop repair, you must fully understand schematics, where all the signals come from and where to go. Today’s laptops are less and less with programmed EC, Dell 1525 has no programmed EC so it can be replaced with same model.
Doing routine check: 1. system power: 3V, 5V all presented – ok 2. NBSWON signal: 3.3V presented – ok 3. press power button, NBSWON pull down to 0V, ok 4. check DNBSWON while press power button, no response. – problem. in here I made a mistake, I didn’t pay attention of the voltage of DNBSWON, this mistake waste me the next few days time. It should be 3.3V, but only about 1V.
Change EC as usual, because I thought the EC has problem. Then the big trouble comes – it auto power up once I plug in the power but stop in 0.04A current. Check and find no S5_ON signal, which indicate south bridge has problem, so change south bridge. But still same problem and still no S5_ON. I find that the EC I change is kb3926A rather than kb3926C. In most case, this is no problem but in very rare occation… So I find a 3926C and put on. Now the motherboard is back to the same problem while I first start to check! So I change a wrong EC and this time I change a correct one, and also EC has no problem!
Because EC will start to read bios once the power plug in(not as people think, once you press power button). I check BIOS chip, BIOS_CS should have a countinue wave form but it just one stright line. BIOS chip is faulty, I replace the BIOS chip and it works perfect.
Okay, so the USB ports seem totally dead, no power at all. It is because some soda was spilled on it (I presume, at least, may be randomly related with something else). I also corrupted my OS X install, have to reinstall freshly. Now, I haven’t reset the SMC or PRAM yet, and that’s the first thing I’ll do (however as there’s is no 5V power, I doubt this will fix it, correct me if I am wrong). However, if that goes sour, and won’t fix the problem, what are my options? Here’s how I was thinking:
Firstly, can someone tell me all the devices I should be seeing in the system profiler under USB? Also, isn’t it so that a central USB controller also handles the internal keyboard and iSight which still work perfectly, meaning that only the ports themselves are damaged? Let’s presume so, and that the USB controller chip is still okay. Should I just replace (desolder old, solder new) the female USB ports, or could the problem lie in the connection between them and the USB controller, and if the latter, how would one go about fixing it?
I think you need to start with the physical USB port/s of the system.Remove the battery pack & disassemble your system. I would clean the area where the soda spilled thoroughly of any soda that might be still present. Use distilled water on cotton swabs (Q-Tips) to clean things…
Chip Level Repair, Chip Level Repairing, Laptop Chip Level Training, Laptop Chip Level Repair.Advanced Circuit Level Troubleshooting and Repairing Of Laptop and Micro Electronics Devices
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